What is ku ku for coco puffs?

Ku ku is the signature catchphrase of Sonny the Cuckoo Bird, the mascot for Cocoa Puffs cereal. The phrase was first introduced in a 1962 advertisement and has since become a well-known part of American advertising vernacular. It is often used to humorously convey a person's extreme desire or craving for Cocoa Puffs. The character of Sonny has evolved over the years, but his love for Cocoa Puffs and his iconic catchphrase have remained a constant.